Motown—The Musical left my eyes tired. For half of the show, they were glued to the stage; for the other half, they rolled up in disbelief to the farthest reaches of their sockets. Rarely has a Broadway musical offered such extremes of talent and inanity. The mountains are thrillingly high: glorious snatches of more than 50 classic pop songs from the catalogs of such Motown artists as Smokey Robinson, Marvin Gaye, the Supremes, the Four Tops, the Temptations and the Jackson 5. But the valleys are abysmally low. The book sections of the show, in which Motown founder and Motown coproducer Berry Gordy Jr. traces 45 years of his own journey, is a compost heap of dubious history, wooden acting and risible dialogue—Little Berry: “I wanna be Joe Louis!” Pop: “Now son, there already is a Joe Louis. Just keep God inside you and be the best you you can be, and that will make me so proud”—all set beneath a flickering neon halo of self-hagiography.

Motown’s subject matter evokes comparison with the Supremes-inspired biomusical Dreamgirls, especially in its treatment of the sexual-professional relationship between Gordy (Dixon) and Diana Ross (LeKae). But it is closer in spirit to Baby It’s You!, the 2011 flop about girl-group impresario Florence Greenberg. What it has that the latter musical lacked is showmanship on a massive scale. Although the lead actors are hamstrung by Motown’s sub-rudimentary script and direction, the musical numbers set the theater on fire. Choreographed by Patricia Wilcox and Warren Adams—and bolstered by Esosa’s costumes, Natasha Katz’s lighting and Peter Hylenski’s sound—the show’s megamix of hits allows for scene-stealing cameos from members of one of the strongest ensembles I have seen on Broadway.

Standouts in the large cast include Saycon Sengbloh as Martha Reeves, N’Kenge as Mary Wells, Ryan Shaw as Stevie Wonder, Morgan James as Teena Marie, and Eric LaJuan Summers as Jackie Wilson, Rick James and Contours singer Billy Gordon—plus the delightful audience favorite Raymond Luke Jr. as a young Michael Jackson. (Jibreel Mawry plays the role at alternate performances.) What a grand night of entertainment this show could be if it junked its plot and just let these troupers work their magic. Motown’s constellation of secret stars, even in the background, shines brighter than the musical’s self-favored sun.—Adam Feldman